Some are also a combination of the bullet diameter and parent case - .22-250, 6.5-06, 6mm-284, etc. I remember reading Barnes' book "Cartridges of the World" and getting a kick out of the names of some of the cartridges from around the turn of the century. I think my favorite was a cartridge intended for cyclists called the ".32 Velo Dog Revolver".
Cedar Creek
Cedar Creek